Systems and methods for simulating depth of field on a computer generated display

Abstract

A system for simulating depth of field in a computer graphics display is provided according to an exemplary embodiment. The system comprises an image generation circuit configured to generate an image representing a plurality of objects for display on the computer graphics display. The image generation circuit is configured to generate the image using a single blur parameter for each of the plurality of objects that represents both a magnitude of blur and a relative distance with respect to a lens focal distance being simulated by the image generation circuit.

What is claimed is: 
     
       1. A system for simulating depth of field in a computer graphics display, comprising:
 an image generation circuit configured to generate an image representing a plurality of objects for display on the computer graphics display, wherein the image generation circuit is configured to generate the image using a single blur parameter for each of the plurality of objects that represents both a magnitude of blur and a relative distance with respect to a lens focal distance being simulated by the image generation circuit; 
 wherein the relative distance represents whether the object is in a far-field, in-focus, or near-field position with respect to the focal distance; 
 wherein the blur parameter is a base blur parameter value for in-focus objects, a higher value than the base blur parameter value for far-field objects, and a lower value than the base blur parameter value for near-field objects. 
 
     
     
       2. The system of  claim 1 , wherein the blur parameter is a positive value for far-field objects and a negative value for near-field objects. 
     
     
       3. The system of  claim 1 , wherein the computer graphics display is part of a flight simulation system. 
     
     
       4. The system of  claim 1 , wherein the image is generated using a single rendering pass and without the use of either ray tracing or accumulation buffers. 
     
     
       5. A system for simulating depth of field in a computer graphics display, comprising:
 an image generation circuit configured to generate an image representing a plurality of objects for display on the computer graphics display, wherein the image generation circuit is configured to generate the image using a single blur parameter for each of the plurality of objects that represents both a magnitude of blur and a relative distance with respect to a lens focal distance being simulated by the image generation circuit; 
 wherein the relative distance represents whether the object is in a far-field, in-focus, or near-field position with respect to the focal distance; 
 wherein the blur parameter is a base blur parameter value for in-focus objects, a lower value than the base blur parameter value for far-field objects, and a higher value than the base blur parameter value for near-field objects. 
 
     
     
       6. The system of  claim 5 , wherein the blur parameter is a negative value for far-field objects and a positive value for near-field objects. 
     
     
       7. A method of anti-aliasing an image, the image having a plurality of pixels and a plurality of objects represented therein, comprising:
 using an image generation circuit to generate an image representing the plurality of objects for display on the computer graphics display; 
 using properties of the objects to retrieve a blur value and a relative distance for each of a plurality of subpixels of each pixel, wherein the relative distance represents whether an object associated with the subpixel is in a far-field, in-focus, or near-field position with respect to a focal distance of the image;
 determining an anti-aliasing output for one or more pixels based on the blur values and relative distances of the subpixels of the pixel, wherein the anti-aliasing output for each pixel is determined using a non-averaging method such that the blur values of the subpixels are not averaged to determine the anti-aliasing output of the pixel; and 
 providing the determined anti-aliasing output for each pixel; 
 wherein the anti-aliasing output is a base anti-aliasing output for pixels associated with in-focus objects, a lower value than the base anti-aliasing output for pixels associated with far-field objects, and a higher value than the base anti-aliasing value for pixels associated with near-field objects. 
 
 
     
     
       8. The method of  claim 7 , further comprising:
 determining an anti-aliasing color output for each pixel using an averaging method such that color values of the subpixels of the pixel are averaged to determine the anti-aliasing color output of the pixel. 
 
     
     
       9. The method of  claim 7 , wherein the determined anti-aliasing output for each pixel is a blur value for the pixel. 
     
     
       10. The method of  claim 9 , wherein determining a blur value for each pixel comprises selecting the blur parameter of a subpixel that is associated with a closest position of the plurality of subpixels of the pixel within a field of view of the image. 
     
     
       11. The method of  claim 9 , wherein determining a blur value for each pixel comprises selecting a blur parameter associated with a greatest number of subpixels from among the plurality of subpixels of the pixel. 
     
     
       12. The method of  claim 7 , wherein blur value and relative distance are represented using a single blur parameter. 
     
     
       13. The method of  claim 7 , wherein the image is displayed on a flight simulation system. 
     
     
       14. The method of  claim 7 , wherein the anti-aliasing output is a blur parameter representing both the blur value and the relative distance.